A large language family including Chinese
, and Burmese
. The two main branches are the Sinitic
, including the languages of China, and the Tibeto-Burman
to the south.
The monosyllabic and tonal nature of Thai and closely related languages such as Lao (the Taic, Daic, or Tai-Kadai family) makes them look very much like Sino-Tibetan, but it has recently been realized that this is due to borrowing and areal contact, not to common descent. The Thai group is possibly more closely related to Austronesian.
The isolated Siberian language Ket (or Yeniseian) may be distantly related to Sino-Tibetan.
There is also a theory held by some linguists that a very deep and ancient macrofamily can be detected, grouping a number of disparate languages from across the world. Along with Sino-Tibetan, this postulated Dene-Caucasian phylum may also include Basque, Burushaski (in the Himalayas), North Caucasian, and Na-Dene (which includes Navaho).